When you read about nutrients for bone health, the “usual suspects” are calcium, magnesium, vitamin D, and maybe one or two other heavy hitters. But as I’ve often said, there are 20 key nutrients for bone health, and just because some of them are needed only in tiny amounts doesn’t make them any less important. Take boron, one of those often overlooked micronutrients that are so important for optimal bone health.

A “booster” for key bone nutrients

If you’ve never heard of boron’s bone health benefits, you’re not alone — yet science has known for decades that boron has a major impact on how we use some of those key bone macronutrients. It acts as a “booster” for several of the most important bone-builders.

Calcium and magnesium, for example, are powerfully affected by the presence or absence of boron. With too little boron, calcium excretion increases and magnesium uptake decreases — very bad for bones. Ensure adequate levels of boron, though, and these problems rapidly reverse.

In one trial, supplementing with 3 mg/day of boron reduced calcium loss by 44% in women with adequate magnesium — in less than one month! In women with low magnesium, calcium loss was reduced by half as much — but it would’ve been interesting to see how that changed over a longer time frame than the 28 days of the study.

So, what about that other critical bone-building nutrient, vitamin D? If you guessed that boron also helps maintain vitamin D levels, you guessed right! Boron helps the body make more effective use of vitamin D by acting as a stabilizer for this otherwise ephemeral nutrient. The same dose used in the studies on calcium and magnesium produced a 39% increase in vitamin D within about 2 months in boron deficient individuals.

I could go on — at length! — about all the benefits boron offers for not only bones, but also hormone balance, brain health, and anti-inflammatory activity. But you get the idea: Boron is something we need. And if you’re also thinking it’s something the average American diet doesn’t offer enough of, well, you’re right on that score, too. The all too common low consumption of fruits and veggies results in low boron intakes of around 1mg per day in the U.S. Notwithstanding, many studies on human health show the benefits of boron are seen with a dose greater or equal to 3 mg/day.

The do’s and don’ts of dietary boron

Like so many other key nutrients, the key to getting enough boron in your diet is to eat a variety of fresh, whole fruits, vegetables, and nuts. Avocados, apricots, cashews, almonds, dates, peanuts, prunes, raisins, lentils, and hazelnuts are some examples of boron-rich foods and are among the best sources of dietary boron out there.

For those of us who struggle with conditions that limit their access to boron-rich foods — a nut allergy, for instance — supplementing with 3 mg/day of boron has been shown to be both safe and effective.

If there’s one “definitely don’t,” it’s this: Don’t turn to boric acid or borax for dietary supplementation. I’ve seen some sketchy health advice online, and it’s important for people to know: Not all boron is created equal.

In foods, boron is found as borates (various combinations of boron with oxygen), which are generally inert and harmless, but some online outlets have advocated using the forms found in pesticides and cleaning products — boric acid (H3BO3) and sodium borate salts such as sodium tetraborate (borax). Both boric acid and borax are caustic chemicals. Exposure can irritate the eyes, skin, and mucous membranes of the nose and mouth — but consuming them can harm or kill you. Both are illegal to use as an additive in foods for this reason, and there are reports in the medical literature of serious poisonings caused by consuming as little as 21 grams of boric acid (the less toxic of the two).

Online claims about the “health benefits of borax” are based on a poor understanding of ongoing research into whether these boron-containing molecules could be used to kill cancer cells or pathogenic microbes — but this does not mean these substances are safe to eat. So boost your bones with an extra helping of guacamole or peanut butter — and leave the borax in the laundry room!